tools/testing/memblock: fix stale NUMA reservation tests

memblock allocations now reserve memory with MEMBLOCK_RSRV_KERN and,
on NUMA configurations, record the requested node on the reserved
region. Several memblock simulator NUMA tests still expected merges
that only worked before those reservation semantics changed, so the
suite aborted even though the allocator behavior was correct.

Update the NUMA merge expectations in the memblock_alloc_try_nid()
and memblock_alloc_exact_nid_raw() tests to match the current reserved
region metadata rules. For cases that should still merge, create the
pre-existing reservation with matching nid and MEMBLOCK_RSRV_KERN
metadata. Also strengthen the memblock_alloc_node() coverage by
checking the newly created reserved region directly instead of
re-reading the source memory node descriptor.

Finally, drop the stale README/TODO notes that still claimed
memblock_alloc_node() could not be tested.

The memblock simulator passes again with NUMA enabled after these
updates.

Signed-off-by: Priyanshu Kumar <priyanshukumarpu@gmail.com>
Link: https://patch.msgid.link/20260415122731.1768912-1-priyanshukumarpu@gmail.com
[rppt: dropped unrelated changes]
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

Author: 0verflowme

tools/testing/memblock/README

@@ -104,10 +104,7 @@ called at the beginning of each test.
 Known issues
 ============
 
-1. Requesting a specific NUMA node via memblock_alloc_node() does not work as
-   intended. Once the fix is in place, tests for this function can be added.
-
-2. Tests for memblock_alloc_low() can't be easily implemented. The function uses
+1. Tests for memblock_alloc_low() can't be easily implemented. The function uses
    ARCH_LOW_ADDRESS_LIMIT marco, which can't be changed to point at the low
    memory of the memory_block.
 

tools/testing/memblock/TODO

@@ -1,5 +1,5 @@
 TODO
 =====
 
-1. Add tests for memblock_alloc_node() to check if the correct NUMA node is set
-   for the new region
+1. Add tests for memblock_alloc_low() once the simulator can model
+   ARCH_LOW_ADDRESS_LIMIT against the low memory in memory_block

tools/testing/memblock/tests/alloc_exact_nid_api.c

@@ -368,7 +368,7 @@ static int alloc_exact_nid_bottom_up_numa_part_reserved_check(void)
 	max_addr = memblock_end_of_DRAM();
 	total_size = size + r1.size;
 
-	memblock_reserve(r1.base, r1.size);
+	__memblock_reserve(r1.base, r1.size, nid_req, MEMBLOCK_RSRV_KERN);
 	allocated_ptr = memblock_alloc_exact_nid_raw(size, SMP_CACHE_BYTES,
 						     min_addr, max_addr,
 						     nid_req);
@@ -861,8 +861,8 @@ static int alloc_exact_nid_numa_reserved_full_merge_generic_check(void)
 	min_addr = r2.base + r2.size;
 	max_addr = r1.base;
 
-	memblock_reserve(r1.base, r1.size);
-	memblock_reserve(r2.base, r2.size);
+	__memblock_reserve(r1.base, r1.size, nid_req, MEMBLOCK_RSRV_KERN);
+	__memblock_reserve(r2.base, r2.size, nid_req, MEMBLOCK_RSRV_KERN);
 
 	allocated_ptr = memblock_alloc_exact_nid_raw(size, SMP_CACHE_BYTES,
 						     min_addr, max_addr,

tools/testing/memblock/tests/alloc_nid_api.c

@@ -1965,7 +1965,7 @@ static int alloc_nid_bottom_up_numa_part_reserved_check(void)
 	max_addr = memblock_end_of_DRAM();
 	total_size = size + r1.size;
 
-	memblock_reserve(r1.base, r1.size);
+	__memblock_reserve(r1.base, r1.size, nid_req, MEMBLOCK_RSRV_KERN);
 	allocated_ptr = run_memblock_alloc_nid(size, SMP_CACHE_BYTES,
 					       min_addr, max_addr, nid_req);
 
@@ -2412,8 +2412,8 @@ static int alloc_nid_numa_reserved_full_merge_generic_check(void)
 	min_addr = r2.base + r2.size;
 	max_addr = r1.base;
 
-	memblock_reserve(r1.base, r1.size);
-	memblock_reserve(r2.base, r2.size);
+	__memblock_reserve(r1.base, r1.size, nid_req, MEMBLOCK_RSRV_KERN);
+	__memblock_reserve(r2.base, r2.size, nid_req, MEMBLOCK_RSRV_KERN);
 
 	allocated_ptr = run_memblock_alloc_nid(size, SMP_CACHE_BYTES,
 					       min_addr, max_addr, nid_req);